Funding for this research was provided by:
Ministry of Health and Welfare (0820010)
Received: 13 September 2017
Accepted: 12 February 2018
First Online: 20 February 2018
Ethics approval and consent to participate
: All studies on humans described in the present manuscript were carried out with the approval of the institutional review board and in accordance with national law and the current, revised form of the 1975 Declaration of Helsinki. Our institutional review board waived the need to obtain written informed consent from the participants.
: Not applicable.
: The authors declare that they have no competing interests.
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